PROBLEM on Trigonometry 10 September 2012 (Post Morning)
Question for practice 
The following questions are more helpful for class tenth students for all boards.
The following questions are more helpful for class tenth students for all boards.
Questions 31.   If sinA + cosA = 1.Find the value of 3.sinA.cosA
                                    
                          Submit your answer here in the comments or wait for answer
Questions 31.   If sinA + cosA = 1.Find the value of 3.sinA.cosA
                          Submit your answer here in the comments or wait for answer
 
 
 
sinA+cosA=1
ReplyDeletesquaring both the sides, we get,
(sinA+cosA)^2=(1)^2
sin^2A + cos^2A + 2sinA.cosA=1
1+2sinA.cosA=1
2sinA.cosA=1-1
2cosA.sinA=0
cosA.sinA=0/2
cosA.sinA=0........eq.(1)
subs. value of sinA.cosA from eq(1)to 3sinA.cosA, we get,
=3*0
=0
sinA+cosA=1
ReplyDeletes.b.s
(sinA+cosA)^2=(1)^2
sin^2A + cos^2A + 2sinA.cosA=1
1+2sinA.cosA=1
2sinA.cosA=1-1
2cosA.sinA=0
cosA.sinA=0/2
cosA.sinA=0
3sinacosa=0*3=0